菌糠多糖-纳米硒复合物的制备及其对水稻促生效果的研究

为探究菌糠多糖-纳米硒复合物对水稻的促生效果,以茶树菇菌糠多糖为原料,采用抗坏血酸为还原剂制备菌糠多糖-纳米硒复合物,并初步探索其对水稻种子萌发及水稻幼苗生长的影响。结果表明,当茶树菇菌糠多糖占比为10%、Vc与亚硒酸钠的配比为4∶1、反应时间为4 h、反应温度为50℃时,可以获得粒径最小且稳定的菌糠多糖-纳米硒复合物。该条件制备的茶树菇菌糠多糖-纳米硒复合物有一定的体外抗氧化能力,对水稻生长具有明显促进作用,且其促生效果高于单一的菌糠多糖,其中对水稻根部发育的影响尤为显著。进一步研究表明,当水稻幼苗叶面喷施菌糠多糖-纳米硒复合物浓度为20 mg·L^-1时,根和叶中可溶性蛋白含量比对照分别提高了72.62%和27.80%,叶中可溶性糖含量增加了180.87%,叶绿素a、叶绿素b、类胡萝卜素含量分别增加了67%、58%、21%。叶面喷施对水稻的促生效果显著高于根部添加处理。本研究为菌糠多糖在农业领域的推广应用提供了理论与实践参考,同时也为利用外源性物质提高农作物生长提供了依据。

Preparation of Polysaccharide-Nano-Selenium Complex From Agrocybe cylindracea Spent Mushroom Substrate and Its Promoting Effects on Rice Growth

Polysaccharide from Agrocybecylindracea spent mushroom substrate (SMS) was used to prepare polysaccharide-nano-selenium (PNS) by adding ascorbic acid (Vc) as a reducing agent. Meanwhile, the effect of PNS on rice seed germination and the influence of foliar spraying of PNS on rice seedlings were investigated. The results showed that the minimum particle size of PNS with good stability could be obtained at a polysaccharide content of 10%, a ratio of Vc to sodium selenite of 4∶1, reaction time of 4 h, and reaction temperature of 50℃. In vitro, it was shown that PNS had a favorable capacity for antioxidation. Prepared PNS showed significant promotion effect on rice growth, especially on rice root. Further studies showed that both treatments, including foliar spraying and root watering, could enhanced morphological features and increase the content of macromolecules. When the concentration of PNS sprayed on the leaves of rice seedlings was 20 mg·L^-1, the content of soluble protein in root and leaf increased by 72.67% and 27.80%, respectively, the content of soluble sugar in leaf also increased by 180.87%, and the contents of chlorophyll a, chlorophyll b and carotenoid increased by 67%, 58% and 21%, respectively. Additionally, the promoting effect of foliar spraying was significantly higher than that of root watering. This study provided a theoretical and practical reference for the use of exogenous substances to promote crop growth.